Multi-pedestal bell type annealing furnace



Feb. 24, 1970 c. c. BLACKMAN MULTI-PEDESTAL BELL TYPE ANNEALING FURNACE 2 Sheets-$heet 1 Filed April 29. 1968 INVENTOR. COIVII'I C. Blackman Fig./

Feb. 24, 1970 c. c. BLACKMAN 3,497,193

MULTI-PEDESTAL BELL TYPE ANNEALING FURNACE Filed April 29, 1968 2 Sheets-$heet 2 2 I l 1 74 I2: 72

INVENTOR. Calvin. C. Bluckmcn United States Patent 3,497,193 MULTI-PEDESTAL BELL TYPE ANNEALING FURNACE Calvin C. Blackman, 24272 W. Lake Road, Bay Village, Ohio 44140 Filed Apr. 29, 1968, Ser. No. 724,772 Int. Cl. C21d 1/06; F27d 1/00, 15/00 US. Cl. 263-49 Claims ABSTRACT OF THE DISCLOSURE A multiple-pedestal base for a bell type furnace wherein each of the pedestals is facilely removable for repair and can be replaced by a similar pedestal while repair of the original is being accomplished to allow continued operation of the base.

This invention relates generally to bases for bell type annealing furnaces and more particularly to multi-pedestal type bases wherein the pedestals are removeably mounted in the supporting structure.

In many bell type annealing furnace installations, and particularly large installations, multi-pedestal type bases are common. The multi-pedestal base furnaces present no great problems when the equipment associated with each of the pedestals is not extremely complex or extensive or seldom needs repair or replacement. However, as the amount and sophistication of the equipment associated with each of the pedestals has increased, the frequency and extent of required repairs and replacements thereof also has increased correspondingly. Thus, the condition exists that if any particular pedestal or the equipment associated therewith needs repair, the whole furnace must be kept out of operation until such repairs can be made. If the repairs are simple or replacement parts are readily available then no great loss of time is involved. However, in many cases the repairs are extensive, or the parts not readily available, or difiicult to install, necessitating many hours of lost production time from the entire base. It can be readily understood that lost time on a furnace can be extremely expensive, and this is magnified even more when a single base contains a plurality of pedestals each of which is used to support a charge. Extensive loss of time can unbalance schedules, require standby payment to personnel, and in general will result in a certain amount of production loss and can cause some shut-down at other points in a plant, because of the unavailability of the base in the normal flow of materials.

It is therefore a principle object of this invention to provide a multiple pedestal base in annealing furnace installations which allows a continued operation of the base during repair of any particular pedestal.

Yet a more particular object of this invention is to provide an improved base for a bell type annealing furnace of the multi-pedestal type wherein each of the pedestals is individually removable and replaceable to thereby permit replacement of a pedestal for continued operation of the base and wherein the pedestal in need of repair can be removed to a location which is convenient for repairs thereto.

3,497,193 Patented Feb. 24, 1970 These and other objects together with a fuller understanding of the invention may be had by reference to the following description taken in conjunction with the accompanying drawings in which:

FIGURE 1 is a plan view partially in section with parts broken away for clarity of a multi-pedestal bell type annealing furnace installation having one of the pedestals removed therefrom;

FIGURE 2 is the detailed sectional view on an enlarged scale from FIGURE 1 showing a removable pedestal disposed in a base according to this invention;

FIGURE 2a is a partial detail view of a modification of pedestal structure shown in FIGURE 2;

FIGURE 3 is an elevational view partially in section showing another embodiment of a removable pedestal in a base according to this invention;

FIGURE 4 is a detailed sectional view of a portion of still another type of a removable pedestal and support thereof; and

FIGURE 5 is a detailed view similar to FIGURE 4 of yet another removable support pedestal and support thereof.

Referring now to the drawings, and for the present to FIGURE 1, a six pedestal annealing furnace base 10 is shown having removable pedestals 12 according to this invention. Each of the pedestals 12 is adapted to support a charge such as coils of strip or wire which are to be annealed. Conventional inner covers 14 are provided each of which is adapted to cover one of said pedestals and the charge thereon to maintain therein a selected atmosphere during annealing. A single outer cover or furnace 16 is provided which is adapted to overlay the entire base 10 which has a heating means (not shown) to heat the space enclosed thereby so as to perform an annealing operation on the material contained within the inner covers 14. The outer cover 16 and the inner covers 14 may be of conventional design.

The supporting structure of the base 10 and the pedestals 12 are designed so that the pedestals can be remova bly mounted in the base 10. One of the pedestals in fact is shown removed in FIGURE 1. It is to be understood that the furnace would not operated with such a pedestal removed, but this is merely intended to illustrate the appearance of the furnace with a pedestal removed before it has been replaced, either with a substitute or itself repaired and returned.

Turning now to FIGURE 2, the construction of the detachably mounted pedestals is shown together with the associated supporting structure and the base member 10. For each pedestal 12 an annular opening 18 is provided which is bounded by an outer annular wall 20 and a horizontal support ledge 22. The pedestal 12 is disposed within the opening 18 and rests on a gasket 24 interposed between the pedestal 12 and the ledge 22. Since the gasket 24 is in a relatively hot zone of the furnace subjected to elevated temperatures, it is preferred that it be made of heat resisting material such as fibre glass wool, asbstos cloth, fiber glass cloth, or the like.

As was indicated above, the pedestals which support the material to be annealed normally incorporate many different fittings and devices which perform various func tions during the heating and cooling of the furnace during the annealing cycle. Some of these are shown, somewhat diagramatically, in FIGURE 2. For example, it is usually necessary to provide some type of protective atmosphere within the inner cover 14 to surround the charge to prevent oxidation or to control other reactions. Therefore, a gas entry pipe 26 is shown as well as a gas exit pipe 28. In order to accomplish circulation of the gases it is normal to provide a fan shown at 30 which is driven by a motor 32. The temperature is normally recorded by means of a thermocouple 34; and during the cooling cycle it is often desirable to accelerate cooling by providing some type of cooling devices in the base. These cooling devices often are water cooled and hence a water entry pipe 36 is provided as well as a water exit pipe 38. Each of these devices require connection to some external source of supply. Quick disconnect couplings 40 and 42 connect the pipes 26 and 28 respectively to a gas source 44 and a gas exhaust '46. Similarly, quick disconnect cou plings 48 and 50 connect respectively water inlet pipe 36 and water outlet pipe 38 to a water supply line 52 and a water drain 54. A conventional heat protected electric plug 56 is provided to connect the motor to a source of AC power, and a quick disconnect plug 58 connects the thermocouple 34 to a lead wire 60 which lead wire leads to a recording device.

Once the material to be annealed is placed on the pedestal the inner cover 12 is placed thereover and the lower leg or rim 62 thereof extends within the annular space 18 between the outer wall 20 and the outer edge of the base 12. In order to prevent the gas from escaping around this inner cover, some type of seal is necessary. In this embodiment this seal takes the form of an annular sealing ring 64, which is comprised of a loose sealing material 65, surrounded by a flexible heat resisting material 66. This type of seal is disclosed in my copending application Ser. No. 725,043, filed, Apr. 29, 1968 entitled Furnace Sealing Device. Because of the removable nature of the pedestal this type of seal is particularly adapted for use in this invention, although other types may be used.

In order to provide for a positive grasping of the pedestal when it is to be removed, some type of grappling device must be provided. Although there are many forms which this device can take in the disclosed embodiment, a plurality of openings 67 (one of which is shown, in diffuser 68. These serve as the grappling points for crane hooks which are used to raise the bases out of the receiving apertures and move them to the desired location.

As can be seen in FIGURE 2, if for any reason the base must be removed, as for example to repair the motor, or to repair the atmosphere piping, or water piping, or for any reason, the couplings 40, 42, 48, 50, 56 and 58 are disconnected thus completely freeing the base from any external attachments. Crane hooks are inserted in at least two of the grappling eyes 67. The pedestal is then raised out and transported to the desired location. Another pedestal can then be provided and dropped into position and the various couplings made with the pedestal ready for service very quickly. Thus, if there is any damage to any of the pedestals, or any repair work needs to be done, the pedestal can be removed for such repair work and another one replaced so that very little loss of furnace operating time is encountered. Of course, if it is not desired to carry an extra pedestal in stock, a dummy plug can be provided which could be inserted into the opening to seal it and the remaining pedestals in the base used.

Another advantage of the removable pedestal construction is that the pedestal can be transported to any desired location where tools are available to perform whatever work is necessary. Also, the pedestal can be positioned to the most advantageous position for performing the work which facilitates the repair of the pedestal thus lessening the amount of time necessary to make the required repairs in the pedestal. This also amounts to a saving in time.

FIGURE 2a shows a modification of the pedestal of FIGURE 2 in that an annular channel 18a is formed on the pedestal which channel will be disposed in the opening 18 and will contain the sealing medium such as loose material as shown sealing ring. In this embodiment the sealing medium is removed with the pedestal which is advantageous if loose material is used to prevent scattering. Also, this channel may contain a liquid sealing medium. In this embodiment, the gasketing takes the form of three annular rings 24a.

Turning now to FIGURE 3, another embodiment of a removable pedestal designated by reference character 12' is shown. In this embodiment a plurality of vertical support column 69 and tie plates 70 are provided which sustain the major portion of the weight of the pedestal 12'. This is the construction shown in FIGURE 1. As shown, an underlying steel structure designated generally as 71 is provided beneath the pedestal 12 which is secured thereto and removable therewith and which provides the bearing surface and structure integrity of the pedestal for support. In this embodiment, the pedestal is provided with an annular recess 72 into which the lower rim 62 of the cover 14 extends. Thus, instead of sealing between the pedestal and the furnace base structure, the seal is accomplished within the confines of the pedestal itself. This arrangement also allows loose material and liquid to be used as seals which cannot conveniently be used in the embodiment shown in FIGURE 2. However, this has the disadvantage of adding to additional weight of the cover to the main position of the pedestal.

Some type of loose insulation 74 is provided between the pedestal 12 and the base 10 in addition to the gasket 24. This may take the form of fibre glass wool, or asbestos fibres, or the like.

Referring now to FIGURE 4 another mounting structure and base configuration is shown which can be employed with either a ledge mounted pedestal of the type shown in FIGURES 2 and 2a or with the under girder construction of the type shown in FIGURE 3. This embodiment has a base member 10" which has a stepped configuration providing a pair of ledges for bearing surfaces. A pedestal member 12" is similarly stepped so that it rests on this stepped bearing surface. Gasketing 24 and insulating material 74 is also provided. This provides an improved heat barrier construction.

FIGURE 5 shows an additional mounting configuration wherein the base structure 10 has a slanting wall instead of a straight wall and the pedestal member 12" is provided with the complimentary slanting wall. Again, gasketing 24 and insulating 74 are provided. This type of structure will help guide the pedestal into place and locate it as it is being lowered into place. Also, as in the case of FIGURE 4, this is an improved heat barrier construction.

While several embodiments of this invention have been shown and described various adaptations and modifications may be made without departing from the scope of the invention.

What is claimed is:

1. A base for a bell type annealing furnace comprising, a furnace supporting structure, said furnace supporting structure including a plurality of pedestal receiving means, each of said pedestal receiving means including means to removably receive a pedestal, a charge supporting pedestal removably disposed in each of said pedestal receiving means, means subjacent each of said pedestal receiving means disposed to independently support said pedestals, each of said pedestals including at least one device requiring connection to an external source, and releasable connection means disposed to connect said device to said source, each of said pedestals including means for removal thereof from said receiving means, whereby the pedestal can be removed for repair.

2. The invention of claim 1 wherein said means to support each of said pedestals includes vertical column means disposed subjacent the pedestal.

6 3. The invention as defined in claim 1 wherein said References Cited pedestal receiving rneans includes an opening of suflicient UNITED STATES PATENTS S126 to expose to view the lower surface of the pedestal disposed therein 2,414,130 1/ 1947 Wilson 263-47 4. The invention as defined in claim 1 further charac- 5 2,546,697 3/1951 Mumford 26347 terized by each pedestal including means for receiving and 2,834,590 5/1958 Pughsealing an inner cover. 2,875,997 3/1959 Blackman 263-47 X 5. The invention as defined in claim 4 further charac- 1 7 11/1968 Blackmail et terized by a space defined between each of said pedestals and the surrounding furnace supporting structure whereby JOHN CAMBY Primary Exammer to provide for different expansion of the pedestals and Us L the furnace supporting structure. 2 5 

